Content providers such as broadcasters often provide special feature presentations such as sports events, live concerts and first time showings in addition to normal content that they do not want copied by the consumer. It is the exclusive availability of this material that, in part, gives it additional value. Hence, broadcaster can often charge advertisers more for on-air commercial time during these special events.
Currently, broadcasters have no significant control over their content, whether a special presentation or normal content, other than a stem warning about the legal penalties for making copies or re-broadcasting without permission. The use of watermarking or placing a logo in one corner has proven to be of little value in limiting the copying of this type of material.
This situation has led to content being encrypted and sent to the user's equipment where it is decrypted for display; however the analog output on consumer devices presents a problem. The analog output then needs a copy protection scheme applied such as that provided by Macrovision Corporation. The shortcoming of this approach is that Macrovision Corporation's copy protection is easily overcome with a time base corrector.
An issue that results from this is the illicit hacking of the encryption scheme. There have been cases where the encryption scheme for satellite service was compromised for a short period of time.